Often, it is convenient to embed links to network resources within electronic documents. As used herein, electronic documents include e-mail messages, Internet web pages, or other electronically distributable data that may include links to network resources (hereafter linked resource). For example, one may receive an e-mail message including a link to a weekly status report residing on a server, where selecting the link causes an information browser, such as the Internet Explorer Internet browser of Microsoft Corporation of Redmond Wash., to open and display the linked resource.
Unfortunately, the server hosting the linked resource may be down, or there may be communication issues that prevent access to the linked resource. In such circumstance, activating the link, e.g., by clicking on it with a mouse pointer, or otherwise activating the link with a selection tool, generally results in a lengthy time out period before it is determined that the linked network resource is unavailable. For example, the Microsoft Internet Explorer application program may take 30 seconds, or more, before it determines that the linked resource cannot be accessed, and provides an error message.
Various approaches have been attempted to avoid such time outs. The simplistic, and often used solution, is to simply assume all links are valid, on the theory that the electronic document would not have been sent out with invalid links. This is generally not a safe assumption. Another approach has been to encode the received electronic document with a programming language, such as Java Script, Visual Basic, etc., where the electronic document incorporates programming code that automatically attempts to validate links to network resources. However, this approach has problems, since noted above, it may take a long time to confirm unavailability of a resource, and a user may attempt to activate a link, e.g., click-on it or other wise select it, before the link can be verified.